Simple DIY diesel scrubbing?

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chuzzlewit

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A copper pipe picks up diesel from the bottom of the tank. A rubber fuel pipe goes on to an electric fuel pump and thence to a Racor filter and water separator. Diesel is then led back into the tank. Any draw backs?
 
no other than the pipe - by design - does not get to the bottom of the tank - but some way off it.

Remember your diesel engine does this anyway. It circulates far far more fuel than it uses - all of which is filtered.

The Bug etc just blocks the filter.
 
chuzzlewit said:
A copper pipe picks up diesel from the bottom of the tank. A rubber fuel pipe goes on to an electric fuel pump and thence to a Racor filter and water separator. Diesel is then led back into the tank. Any draw backs?
Click to expand...
You may find this useful.

 
I made a fuel polishing system using wider bore piping that I got into the tanks by removing a sender if memory serves. A 12v pump and central heating fuel filters with stainless inserts that can be cleaned. It worked okay.
 
chuzzlewit said:
A copper pipe picks up diesel from the bottom of the tank. A rubber fuel pipe goes on to an electric fuel pump and thence to a Racor filter and water separator. Diesel is then led back into the tank. Any draw backs?
Click to expand...
A better solution if your fuel tanks are like ours.
Princess built small sumps at the bottom of each of our tanks.
Each sump has a small drain cock.
When we caught the bug, after removing the sludge, I connected hoses to the small drain cocks and circulated a strong Marine 16 concentration of fuel back into the inspection hatches using a small pump.
So, yes, you probably could do something like this to scrub your diesel.
I was mainly interested in killing the bug though but it was successful - no bug since.
 
Knock the above up perhaps with a 30 micron, then replace later with a 2 micron spin-on fuel filter with by-pass (used just to treat) should work well. A couple of pressure gauges across the filter to determine when clean/challenged is a bonus... The fuel is filtered anyway as has been said, usually to 2mic on secondaries.
 
chuzzlewit said:
Thanks. That was just about what I mean to do . Making it permanent would avoid mess and let me run it while moving , possibly shaking up sediment.
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While you are moving your fuel is be being cleaned. Follow your fuel system and you will find a "return" to the tank. The pump will draw for example, 10l a minute and you will use 5l, the excess filtered fuel is returned to the tank.
 
Am in the process of knocking one of these up myself.
I have 220l in 2 long range tanks that from what I can gather has been there for at least a couple of years.
This extra weight is the equivalent of 3 of me standing on the bathing platform wondering why she struggles to get up on the plane
 
Hurricane said:
Actually, if you don't have a problem now, I wouldn't bother with any of this DIY polishing.
I've not needed anything since we cured our bug.
But I would treat EVERY delivery of fuel with a bug treatment - I use Marine 16.
In comparison with the cost of the fuel it is peanuts.
Just do it - TREAT YOUR FUEL
Click to expand...
I have a brief history of working in pharmaceutical. Every micro organisms (bugs) have a habit over time of becoming immune to the chemical treatment to kill them, so we used to rotate 3 different types of disinfectant.
For this reason I alternate every other fill.
Marine 16 which kills the bug, it doesn’t remove it but it does not go jellified and is consequently filtered out. This is the brown rust like gritty small deposits seen in the bottom of the filter bowl.
Fuelset. Which disperses the water where the bug grows at the demarcation.
This info I think I got from PBO article a few years ago
 
chuzzlewit said:
A copper pipe picks up diesel from the bottom of the tank. A rubber fuel pipe goes on to an electric fuel pump and thence to a Racor filter and water separator. Diesel is then led back into the tank. Any draw backs?
Click to expand...
That’s what I did. It works well. I also got the bug in spite of treating with a biocide.
 
Rocksteadee said:
I have a brief history of working in pharmaceutical. Every micro organisms (bugs) have a habit over time of becoming immune to the chemical treatment to kill them, so we used to rotate 3 different types of disinfectant.
For this reason I alternate every other fill.
Marine 16 which kills the bug, it doesn’t remove it but it does not go jellified and is consequently filtered out. This is the brown rust like gritty small deposits seen in the bottom of the filter bowl.
Fuelset. Which disperses the water where the bug grows at the demarcation.
This info I think I got from PBO article a few years ago
Click to expand...
Yep, I read the same article before sorting our bug case.
I have copies if anyone is interested.

I have absolutely no background in chemistry or pharmaceuticals.
But, during the bug cleaning process, I did a test.
I filled a large water container (8 litre size I think) with the crud that came off the bottom of the fuel tanks (sumps).
It was a black sticky sludge.
I added about a thimble full of Marine 16 to the container and shook it up.
Then left it overnight.
In the morning the whole bottle was clear except for about a quarter of a teaspoon of small particles in the bottom.
I'm sure that the particles would have been caught in the filters and certainly not enough to block the filters.
I take your point about micro organisms becoming immune but I will be continuing to use Marine 16 every time.
I believe that the fuel suppliers use some form of mass treatment in the supply chain.

Here is a copy of an article that I wrote for MBY when we cleaned our tanks after our bug case.
It may be interesting to some people.

The-Bug-Bites.resized.jpg
 
I have a background in the aviation fuel industry where the bug is a bit more concerning, In the end it comes down to house keeping ,keep the fuel water free and there can be no bugs, drain your tanks regularly remove water from water traps/sedimentors as it occurs.
 
Freebee said:
I have a background in the aviation fuel industry where the bug is a bit more concerning, In the end it comes down to house keeping ,keep the fuel water free and there can be no bugs, drain your tanks regularly remove water from water traps/sedimentors as it occurs.
Click to expand...
My bug attack was immediately after refuelling.
Nothing before - bug after.
 
I reckon most marina fuel tanks in the Med get the bug at some stage, their lower fuel turnover this year may exacerbate the problem. I expect some may treat their tanks.

I did start rotating treatments for the reasons stated above on my first boat as I thought it made sense, but must say in recent years I have only used Marine 16 on my F43 and now my P45 and am really happy with it. I may though knock up a rig at some stage myself as I would be interested in the results...…
 
I've always had a 'thing' about on board polishing systems. Why?
  1. Your engines polish your fuel whenever they are running by returning excess fuel to the tanks, having already polished it through your primary and secondary filters. The longer the engines run, the more the fuel is polished.
  2. The real issue is dead bug and any water which accumulates at the bottom of the tank.
Most bug issues occur in emotional seas when it's stirred up and sucked into the fuel lines.

Hence, a polishing system needs a powerful pump to draw fuel from well above a tank's base and suck it through a filter system before forcing it at a strong flow rate aimed at the tank's base to stir up 'whatever' may be lurking there. 'Whatever' is strirred up, sucked through the filter system, etc, etc. with the cycle repeating itself until all the water and bug sediment has been trapped in the filter system.

Recreational boats would normally use a set of Racor filters. Larger boats will use a centrifugal pump, one of the smallest being from Alfa Laval.

I wanted to fit one to Play d'eau, but the piping would mean major (and I mean major) surgery on the tanks. However, using Grotomar 82 for years, and checking the sumps, has resulted in zero water and dead bug.
 
Piers said:
I've always had a 'thing' about on board polishing systems. Why?
  1. Your engines polish your fuel whenever they are running by returning excess fuel to the tanks, having already polished it through your primary and secondary filters. The longer the engines run, the more the fuel is polished.
  2. The real issue is dead bug and any water which accumulates at the bottom of the tank.
Most bug issues occur in emotional seas when it's stirred up and sucked into the fuel lines.

Hence, a polishing system needs a powerful pump to draw fuel from well above a tank's base and suck it through a filter system before forcing it at a strong flow rate aimed at the tank's base to stir up 'whatever' may be lurking there. 'Whatever' is strirred up, sucked through the filter system, etc, etc. with the cycle repeating itself until all the water and bug sediment has been trapped in the filter system.

Recreational boats would normally use a set of Racor filters. Larger boats will use a centrifugal pump, one of the smallest being from Alfa Laval.

I wanted to fit one to Play d'eau, but the piping would mean major (and I mean major) surgery on the tanks. However, using Grotomar 82 for years, and checking the sumps, has resulted in zero water and dead bug.
Click to expand...
Why do you say "well above the tank's base"?
 
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